Task<string> SummarizeAsync(
    RichEditDocumentServer wordProcessor,
    SummarizationMode mode = SummarizationMode.Abstractive,
    CancellationToken cancellationToken = default(CancellationToken)
)

Function SummarizeAsync(
    wordProcessor As RichEditDocumentServer,
    mode As SummarizationMode = SummarizationMode.Abstractive,
    cancellationToken As CancellationToken = Nothing
) As Task(Of String)

using DevExpress.AIIntegration.Docs;
using DevExpress.XtraRichEdit;
using DevExpress.XtraRichEdit.API.Native;

// See "Register AI extension service" section for implementation code
var docProcessingService = defaultAIExtensionsContainer.CreateAIDocProcessingService();

var wordProcessor = new RichEditDocumentServer();
wordProcessor.LoadDocument("Documents/FirstLookShortened.docx");
string summary = await docProcessingService.SummarizeAsync(
    wordProcessor,
    SummarizationMode.Extractive,
    CancellationToken.None);

wordProcessor.Document.Paragraphs.Insert(wordProcessor.Document.Paragraphs[0].Range.Start);

Paragraph summaryParagraph = wordProcessor.Document.Paragraphs[0];

// This method resets formatting for the inserted paragraph
ClearFormatting(summaryParagraph);

wordProcessor.Document.InsertText(
    summaryParagraph.Range.Start,
    "Document Summary:\n" + summary);
wordProcessor.SaveDocument("Documents/SummarizationResult.docx", DocumentFormat.Docx);

void ClearFormatting(Paragraph paragraph)
{
    CharacterProperties cp = wordProcessor.Document.BeginUpdateCharacters(paragraph.Range);
    cp.Reset();
    cp.Style = wordProcessor.Document.CharacterStyles["Normal"];
    wordProcessor.Document.EndUpdateCharacters(cp);
    ParagraphProperties pp = wordProcessor.Document.BeginUpdateParagraphs(paragraph.Range);
    pp.Reset();
    pp.Style = wordProcessor.Document.ParagraphStyles["Normal"];
    wordProcessor.Document.EndUpdateParagraphs(pp);
}

Imports DevExpress.AIIntegration.Docs
Imports DevExpress.XtraRichEdit
Imports DevExpress.XtraRichEdit.API.Native
Imports System.Threading.Tasks
Imports System.Threading

Async Function Main() As Task
    ' See "Register AI extension service" section for implementation code
    var docProcessingService = defaultAIExtensionsContainer.CreateAIDocProcessingService()

    Dim wordProcessor As New RichEditDocumentServer()
    wordProcessor.LoadDocument("Documents/FirstLookShortened.docx")
    Dim summary As String = Await docProcessingService.SummarizeAsync( _
        wordProcessor, _
        SummarizationMode.Extractive, _
        CancellationToken.None)

    wordProcessor.Document.Paragraphs.Insert(wordProcessor.Document.Paragraphs(0).Range.Start)

    Dim summaryParagraph As Paragraph = wordProcessor.Document.Paragraphs(0)

    ' This method resets formatting of the obtained paragraph
    ClearFormatting(wordProcessor, summaryParagraph)

    wordProcessor.Document.InsertText( _
        summaryParagraph.Range.Start, _
        "Document Summary:" & vbLf & summary)
    wordProcessor.SaveDocument("Documents/SummarizationResult.docx", DocumentFormat.Docx)
End Function

Sub ClearFormatting(wordProcessor As RichEditDocumentServer, paragraph As Paragraph)
    Dim cp As CharacterProperties = wordProcessor.Document.BeginUpdateCharacters(paragraph.Range)
    cp.Reset()
    cp.Style = wordProcessor.Document.CharacterStyles("Normal")
    wordProcessor.Document.EndUpdateCharacters(cp)
    Dim pp As ParagraphProperties = wordProcessor.Document.BeginUpdateParagraphs(paragraph.Range)
    pp.Reset()
    pp.Style = wordProcessor.Document.ParagraphStyles("Normal")
    wordProcessor.Document.EndUpdateParagraphs(pp)
End Sub

case RichEditDocumentPart.WholeDocument:
    summaryText = await docProcessingService.SummarizeAsync(wordProcessor, summarizationMode);
    break;